Elevator system



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ELEVATOR SYSTEM Filed Sept. l?, 1938 6 Sheet's'heet 3 U) ,U2 D2 im (505 (ua 1,0/1 l)U5 1,05 ,u@ lp() (m OTE() I zsm) CM() CARZ CAR?) CARA CAR) [A22 CAS3 CARA v l l 5 CAR) *Mn-1H) 7 47u) 51(2) 47(5) 47(4) To) 5)() 57(2) 57(5) 57(4) CAm (52(4))52 CAM/CARA ou) 55(1) 5?(1) 55(5) 55(4) @WM- (l) (i) (3) (L1) PU( PUZ DUZ PUZ (l) (Z) (5) (4) PRN) PRKZ) PRUB) PRN() a? i) 2)/ E? )gg BY ATTORNEY 17, 1940. yV. F. @LASER 2,215,998

ELEVATOR SYSTEM Filed sept. 17. 193s 6 shee-heet 4 D/Gxm v @pus mm2 mm1 DLIsm /sm um |22 2G11 NSZ KLM DUS pob

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puf] AVU PD? 05 n f ETFASNA 13mg/ f-IG, 3 WM wjf @M2M INVENTOR BY 'Hummm l ATTORNEY 6 Sheets-Sheet 6 ATTORNEY 5Pt 17, 1940. w. F. GLAsr-:R

ELEvAToR sYs'gEu Filed Sept. 17 1958 Patented Sept. 17, 1940 PATENT OFFICE ELEYATOR SYSTEM William Frank Glaser, Eastchester, N. Y., asslznor to Otis Elevator Company, New York, N. Y., a

corporation of New yJersey Application September 17, 1938, Serial No. 230,461

21 Claims.

The invention relates to elevator systems.

The form. of elevator control 'to which the invention especially relates is one in which the starting of the elevator car after each stop is under the control of an attendant in the car, while the stopping of the car is automatic, stops to discharge passengers being made in response to push buttons within the elevator'car operated by the attendant as directed by the passengers, and stops to take on passengers being made in response to push buttons at the landings operated by the intending passengers themselves. With such control applied to a plurality of elevator cars, push buttons at the landings are common to the cars.

In many buildings to which such control is applicable, a peak demand arises at one or more periods during the day for elevator service. to depopulate the building. The invention is especially directed to the control of the elevator cars during such a period and it is an object of the invention to cause operation of the elevators during such time in such way as to provide maximum traflic handling capacity with equal service to all portions of the building.

The invention involves causing the elevators to serve different zones of the building. Each zone comprises certain oors of the building and has certain cars assigned to it. Elevator systems to which the invention is applicable and in connection with which it will be described are very complex. As an aid `to an understanding of the principles and features of the invention, operation of an embodiment of the invention chosen to illustrate these principles and `features will be outlined.

During the period of peak demand for elevators to depopulate the building, each car upon arriving at the lower terminal and discharging its passengers is started immediately by its car attendant, running to the highest oor in its zone for which a down hall call is registered. Upon picking up such a call, the car is slowed down and brought to a stop and automatically set for travel in the down direction. During its downward trip it stops in response to down calls until lled to capacity, whereupon the attendant by-passes further hall calls and the car runs express to the lower terminal. Preferably each car is responsive to car calls during this time, regardless of the direction of travel for which it is set. Also, certain cars, preferably those serving the upper zone, may be responsive to up hall calls when set for upward travel. However, since there is very little inter-door trailic during such period, each car usually runs express to the highest down hall call in its zone and after picking up this call travels downwardly, picking up down hall calls for floors below. Each car serves the floors in its own zone first and then, if there is space left in the car, assists the cars in the lower zones in taking on outgoing passengers until it is filled to capacity. Thus, not only is adequate service assured for all oors of the building, but the elevator system is utilized to its maximum passenger handling capacity so as to depopulate the building within a minimum of time.

Other features and advantages will become apparent from the following description and appended claims.

In the drawings:

Figure 1 is a simplified schematic representation of an elevator installation in accordance with the invention;

Figures 2a and 2b, taken together, constitute a simplified wiring diagram of the push button control circuits and the, call pick up and call restoring circuits for a plurality of elevators in accordance with one embodiment of the invention;

Figure 3 is a simplied wiring diagram of the power and control circuits for one of these elevators; and

Figures 2s and 3s are key sheets for Figures 2a. and 2b and Figure 3 respectively, showing the electromagnetic switches in spindle form with the contacts and coils on the spindles in horizontal alignment with the corresponding contacts and coils on the wiring diagram.

For a general understanding of the invention, reference may be had to Figure 1, wherein various parts of the system chosen to illustrate the principles of the invention are indicated by legend. Four elevators are illustrated, with the cars at different floors in the hatchway. The arrangement is the same for each elevator. Each car is raised and lowered by means of a hoisting motor, which motor drives a traction sheave over which pass hoisting ropes for the car and counterweight. An electromagnetic brake is provided and is applied to eiect the final stopping operation and to hold the car when at rest.

Each elevator c ar is provided with a car operating panel on which are located a plurality of control switches for operation by the car attendant. These switches include a start control switch, a plurality of push buttons, one for each floor above the lower terminal, hereinafter termed car buttons, a safety switch and a non-- stop switch. These switches are shown in the wiring diagrams of Figures 2b and. 3.

At each iloor is a push button box within which are arranged push buttons, an up and a down push button at each intermediate o'or and one push button at each terminal floor. These push buttons, which will hereinafter be termed hall buttons, are common to the cars.

Reference may now be had to Figures 2a, 2b and 3, which illustrate diagrammatically the various control and power circuits. Figures 2a and 2b show the push button control circuits and the call pick up and call restoring circuits for four elevators, a seven floor installation being indi-l cated. The circuits of Figures 2a and 2b are joined by wires ISG), |8(2), I8(3) and ISM), which extend from one ligure to the other crosswise of the diagrams. Figure 3 shows the starting and stopping circuits and power circuits for one elevator, it being understood that such circuits are provided also for the other three elevators.

The control system illustrated has been considerably simplied. Such system has been vshown because it facilitates disclosure of an application of the invention. It is to be understood that other control elements and safety elements may be added in making up the system and that such system is subject to many variations. For example, the invention may be applied to the control system disclosed in the patent to Waters and Glaser No. 2,074,575, dated March 23, 1937.

Ihe electromagnetic switches employed in the system illustrated are designated as follows:

ASM- Auxiliary stopping switch 13K-Brake resistance relay BR-Brake E-Speed switch EIA-Auxiliary speed relay I-I-Field and brake switch NS-Non-stop relay OS-Operating switch sequence relay PD-Down direction switch PR-Auxiliary direction relay PU-Up direction switch SM-Stopping magnet XC-Highest car call relay XH-Automatic return relay XSD-Highest down hall call relay KSU-Highest up hall call relay ZS-Zone switch Throughout the description which follows, these letters will be applied to the coils of the above designated switches. Also, with reference numerals appended thereto, they will be applied to the contacts of these switches. Differentiation will be made between the different elevators by appending in Figures 2a and 2b to the characters employed to designate the various elements of the control system numbers indicative of the different elevators and arranged in brackets, as done above for cross wires 8.

The up hall buttons are designated U, while the down hall buttons are designated D. Numerals are appended to these letters indicating the iioors for which the buttons are provided, the letter T being appended to the down hall button at the top oor instead of a number. The hall buttons are common to all of the elevators and act through oor relays designated first by the numeral corresponding to the iloor for which the door relay is provided and then by the letter U or D in accordance with whether the floor relay is for an up hall button or a down hall button. The car buttons are designated C and, as in the case of the hall buttons, have numerals appended thereto as indicative of the' ters numbers in brackets.

The circuits are shown in straight or across the line form, in which the coils and contacts of the various switches are separated in such manner as to render the circuits as simple and direct as possible. The relationship of these coils and contacts may be seen from Figures 2s and 3s, where the switches are arranged in alphabetical order and shown in spindle form. The positions of these coils and contacts in the wiring diagram may be found by referring to Figures 2s and 3s, where the coils and contacts are positioned on the spindles in horizontal alignment with the corresponding elements of the wiring diagram. The electromagnetic switches are illustrated in deenergized condition, direction switches PU and PD, which are of the latching type, being shown in reset condition.

Mechanism actuated in accordance with movement of Jthe elevator car is utilized in the control circuits of each elevator. Such mechanism may be in the form of a door controller or selector machine as indicated in Figure 1 and it will be assumed that the mechanism is o! the construction shown in the aforementioned patent to Waters and Glaser No. 2,074,575. Details of this mechanism are not shown as such details are given in the Waters and Glaser patent, to which reference may be made.

Each selector machine is driven preferably by means of two steel tapes attached to the car. One tape extends from the top of the car to an overhead sheave. The other tape extends from the bottom oi.' the car around a tension sheave and then up to a second overhead sheave. The tapes are wound on the overhead sheaves in a manner similar to the winding of a measuring tape, one being wound oppositely with respect to the other. The shaft upon which the overhead sheaves are mounted drives the selector machine through a chain and sprocket. One tape is unwound as the other is wound up in effecting the driving operation.

Each selector machine comprises a crosshead which is driven by a screw, which is in turn driven by the chain and sprocket, to move in accordance with movement of the car for which the machine is provided. The crosshead carries a carriage upon which is mounted mechanism for controlling circuits to cause the car to be slowed down and stopped at a oor. Mechanism is also mounted on the carriage for causing slow down to begin at a certain distance from the oor and for causing the car to be brought to a stop as it arrives at the iloor. The carriage is advanced from a neutral position with respect to the crosshead in starting the car and is brought to a stop after a certain amount of movement. Thereafter the carriage moves with the crosshead. When circuits are set up to cause the car to be slowed down, the carriage is brought to a stop. The crosshead, which moves with the car, thereafter takes up of this motor appear in Figure 3 where the motor is designated AM. Energization of the advancer motor is controlled by contacts oper-y ated by the stopping magnet. The circuits of this magnet appear in Figures 2a and 3 where the magnet is designated SM. The magnet controls the extension and retraction of pawls carried by the carriage for cooperation with stopping lugs. A stopping lug is provided for each fioor\and is arranged on a floor bar, these oor bars being spaced in accordance with the distance between the floors for which the lugs are` provided. The stopping magnet is energized in the starting operation to effect the retraction of the pawls and in doing so it engages contacts to effect the energization of the advancer motor. The advancer motor in advancing the carriage also effects the engagement of selector switches appearing in Figure 3 and designated SSI and SSZ. When a call is picked up the stopping magnet is deenergized to cause the deenergization of the advancer motor and to extend the pawls for cooperation with the stopping lug for the floor for which the call is registered. 'I'he pawl for the direction in which the car is travelling engages the stopping lug, bringing the carriage to a stop. The crosshead continues its upward movement and due to the relative movement between the crosshead and the carriage, effects the opening of selector switches SSZ and SSI in sequence to eiect the slow down and stopping of the car.

The travelling brushes for each elevator illus-y trated in Figures 2a and 2b are carried by a panel on the carriage of the selector for that elevator. These brushes are arranged to cooperate with stationary contacts for the various floors arranged on the floor bars. When the car is stopped at a floor, the brushes are in engagement with their cooperating stationary contacts for that iloor. Being on the advance panel, however, these brushes are advanced in starting the car, are latched in engagement with their contacts for a floor by the pawls when a call is picked up and are maintained in that condition as the advance is taken up as the car comes into the floor.

As in the case of the electromagnetic switches, differentiation between the corresponding elements of the selectors for the diiTerent elevators in Figures 2a and 2b is made by appending numbers in brackets to the characters employed for these elements. Also, legends Car 1, Car 2, Car 3 and Car 4 are applied to Figures 2a and 2b as a further aid in distinguishing between the mechanisms for the different elevators. Sta-v tionary contacts subject to the car buttons are designated 32, 33, 34, 35 and 38 foriioors 2, 3, -4, 5 and 6 respectively, the stationary contacts 3| and 31 for the rst and seventh floors being connected directly to the feed line. These contacts are engaged by brush 38. Instead of providing brushes and contacts for the call restoring circuits separate from those for the call pick up circuits, as is disclosed in the aforementioned Waters and Glaser patent, for convenience the same contacts and brushes are used for both cirrality of hook switches 82, 83, 84, 85 and 88, one ,30

cuits 'with a switching arrangement to insure the desired sequence of operation. Itis to be understood, however, that the same arrangement as disclosed in the Waters and Glaser patent may be employed. The stationary contacts subject-3 to the down hall buttons at the second, third, fourth, fifth, sixth and seventh floors and the stationary contact for the first floor in the call pick up and call restoring circuits are designated 4|, 42, 43, 44, 45, 45 and 41 for'the rst, second, 10

third, fourth, fifth, sixth and seventh floors respectively. 'I'hese contacts are engaged by brush 48. The stationary contacts subject to the up hall buttons at the first, second, third, fourth, v

-ilfth and sixth floors and the stationary con- 1 tact for the seventh floor in the call pick up and call restoring circuits are designated 5|, 52, 53, 54, 55, 58 and 51 for the first, second, third, fourth, iifth, sixth and seventh floors respectively. These contacts are engaged by brush 58. contacts82, 83, 84,'85`and 88 for the second, third, fourth, fth and sixth floors respectively are arranged in the highest up hally call circuits to be engaged by brush 88. Also, stationary contacts 12, 13, 14, 15 and 18 are arranged in the 25 highest down hall call circuits to be engaged by brush 18.

As shown in Figure 2a, each selector has a plufor each of floors 2, 3, 4, 5 and 6, arranged on the floor bars for these floors to be engaged by a travelling cam 88 of insulating material also carried by the advancer panel. This cam is of a length to engage and open the hook switch for r any particular floor zslightly ahead of the engagement of the call pick up brushes with the stationary contacts for that floor when the car is travelling in the up direction and to engage and open the hook switch for the floor below such I iloor slightly ahead of the engagement of the 40 call pick up brushes with the stationary contacts for such iloor when the car is travelling in the down direction. Also, the brushes 68 and 18 in the highest hall ,call circuits are of a length to engage their stationary contacts slightly ahead 45 of the engagement of the call pick up brushes with their contacts for the corresponding iloors y when the car is travelling in the up direction.

The travelling crosshead of each elevator also 7 carries an additional brush 80 (see Figure 3) on '50 a panel separate from the advancer panel for engaging stationary contacts 8| and 92 for the terminal floors. T'his has to do with controlling the operation of direction switches PU and PD. An

additional hook switch |22 (see Figure 3) is '55 provided on the selector machine. This switch may be arranged to be operated by cam 88(|) so as to be open when the car is at the first iloor and closed when it leaves the rst floor. For convenience, however, a separate cam |23 (arranged on the advancer panel) is illustrated for operating this switch.

Any suitable form of power supply may be provided for the elevator motor. One of the preferred arrangements is to employ a direct cur- 6 rent elevator motor and to cause current to be supplied to the motor at a variable voltage, as from a driven generator in accordance with Ward-Leonard principles. The generator of such arrangement has been illustrated. The driving 70 motor for the motor generator set and control arrangement therefor have not been illustrated. It is to be understood that either a direct current or alternating current driving motor may be employed, depending upon the kind of power Stationary 20 supplied to the building and the character oi' the installation, and that any suitable control arrangement therefor may be utilized, such, for example, as one embodying the principles of the arrangement disclosed in the patent to Lindquist, Waters and Glaser No. 1,997,260, granted April 9, 1935.

When the generator` is driven by an alternating current driving motor, an exciter which may be driven by the driving motor is employed to supply current to the separately excited iield windings of the supply generator and the elevator motor and to the brake and the coils of the various electromagnetic switches of Figure 3. In such arrangement, the supply lines of Figure 3 would be connected to the exciter. Also, the call pick-up and call restoring circuits and highest call circuits for each elevator would be connected to the respective exciters. The hall button circuits through the operating coils of the floor relays, however, would be connected to the source of supply for the building so as to permit the operation of the floor relays at any time. In case of direct current power supply, the supply lines of Figures 2a, 2b and 3 would be connected to the power supply lines. For convenience, it will be assumed that direct current is supplied to the building.

The armature of the generator is designated S5, the separately excited iield winding being designated 96 and its series iield winding til. The armature of the elevator motor is designated 98 and its separately excited eld winding |00. A resistance is provided for controlling the strength of the generator separately excited field and therefore the voltage applied to the elevator motor armature. |02 is a discharge resistance for the brake release coil BR, while resistance |03 serves as a cooling resistance for this coil.

The contacts operated by the car gate and engaged when the gate is closed are designated G. The door contacts operated by the various doors are arranged in series relation. These contacts are not closed until the doors are closed and locked. For convenience these door contacts are shown as a single pair of contacts designated DL. The car gate and hatchway doors for each elevator have not been shown but it is to be understood that they may be power operated, for example as disclosed in the aforementioned patent to Waters and Glaser, No. 2,074,575. The start control switch in the car has a plurality of contacts designated |05, |06 and |01. ||0 is the safety switch in the car. ||3, |20, |2| and |24 are service switches. It will be assumed that the service switches are in the positions illustrated.

The operation of the control system illustrated will now be described. It will be assumed that elevators Nos. 1- and 2 serve iioors 5, 6 and 7 for outgoing traiiic, whereas elevators Nos. 3 and 4 serve oors 2, 3 and 4 for outgoing traffic. The system is illustrated for the condition Where all cars are standing at the iirst iioor. To facilitate understanding of the system, the starting and stopping of car No. 1 will rst be described. Assume now that the power is applied to the system. This completes a circuit for the coil of elevator No. 1 highest car call relay XC(|), this circuit being from line through contacts XSD|(|) and by way of wire ||2(|) through service switch |2|( and hook switches 85H) and 86(|), in parallel with contacts XSDI (l), to line It also completes the circuit ror the coil of elevator No. 1 non-stop relay NSU) through elevator No. 1 non-stop button NSBU). Relay XC upon operation separates contacts XC|(|) and XC2. Contacts CHI) are' in the circuit for brush 68(|)` in the highest'up hall call circuits, disconnecting this brush from. line Contacts X02 are in the circuit for the coil of automatic return relay XH. Relay NS upon operation engages contacts NSIU) and separates contacts NS2. Contacts NS|(|) control the circuits for the brushes 46(|) and 66H) in elevator No. 1 call pick-up and call restoring circuits. 'Ihe separation of contacts NS2 removes the by-pass for contacts XSD2, XSUI, ASM3 and EA2 in the circuit for the coil of automatic return relay XH. The application of power to the system also energizes elevator motor field winding ion.

When car No. 1 last arrived at the first floor, brush 90 engaged stationary contact 92 and, upon the engagement of contacts Hl in the stopping operation, a circuit was established for the reset coil of down direction switch PD and for the operating coil of up direction switch PU. This caused the down direction switch to be reset, the condition in which it is shown in the drawings, and the operation of switch PU and latching of this switch in operated condition. The operation of switch PU caused the engagement of contacts PU|(|), PU2(|), PU3, PUI, PU5, PUT, PUB, PUQ, PU|0 and PU|| and the separation of contacts PUG. Contacts PU|(|) are in the circuit to brush 6(|) this circuit being broken by the separation of contacts XCI (l) as above described. Contacts PU2(|) connect brush 18( l) to line through the coil of highest down hall call relay XSDU). Contacts PU3 are in the circuit for the coil of automatic return relay XH, the establishment of this circuit being prevented by hook switch |22 being open. Contacts PU4 are in the circuit for lamp |35 in the elevator car and the coil of auxiliary direction relay PR. Thus, upon the application of power to the feed lines, the lamp in car No. 1 is illuminated and the auxiliary direction switch PR is operated. Contacts PUS are in the circuit for car button magnet CBM so that this magnet is energized upon the connection of the feed lines with the source of current supply. Contacts PUG disconnect the operating coil of up direction switch PU and the reset coil of down direction switch PD from the feed lines. Contacts PUT connect field winding AM|25 and armature AM|26 of the advancer motor in parallel. Contacts PUB control the circuit for the coil of brake and eld switch H and contacts PUB control of the circuit for the coil of speed switch E. Contacts PU|0 and PU|| prepare the circuit for the generator separately excited iield Winding 56 for upward travel of the elevator car.

Auxiliary direction relay PR upon operation separates contacts PRIN) and engages contacts PR2(|). The separation of contacts PR|(|) renders down hall call brush 48H) ineffective for up car travel, while the engagement of contacts PRZU) renders the up hall call brush 58(|) eilective for up car travel.

To start the car, the start controlswitch for car No. 1 is thrown to full running position. This causes the bridging of contacts. |05, |06 and |01, contacts |06 being bridged ahead of contacts |05 and |01. The bridging-of contacts |06 completes circuits (not shown) causing the closing of the car gate and first floor hatchway door. It also completes a circuit for the operating coil of stopping magnet SM through contacts OSI and EAI. 'I'he stopping magnet upon operation engages contacts SMI(I), SM2 and SMS. Contacts VYSMI(I) are in the circuit for the neutralizing coil SM(I) of the stopping magnet. Contacts SMI complete a holding circuit for the operating :oil of the stopping magnet. Contacts SM2 complete a circuit for the coil of auxiliary stopping switch ASM and for one coil of auxiliary speed relay EA. Relay EA does not operate at this time. Switch ASM operates to separate contacts ASM2(I) and to engage contacts ASMI (I), ASM3 and ASMl. Contacts ASM2 are in a bypass circuit for the neutralizing coil SM(I) of the stopping magnet. Contacts ASMI are in the circuit for the coil of automatic return relay XH. Contacts ASMIU) are in the circuit from brush 38H) to coil SM(I). Cntacts ASMI prepare the circuit for the advancer motor AM, which is completed by the bridging of start control switch contacts I05, this circuit being through field winding AMI21 and through field winding AMI25 and armature AMI26 in parallel. This results in the operation of the advancer motor to advance the carriage in the up direction. The advancer motor also effects the engagement of selector switches SSI and SS2, preparing the circuits for the coils of field and brake switch H and speed switch E and completing the circuit for a second coil of auxiliary speed relay EA.

The energization of both coils of relay EA causes this relay to operate to engage contacts EAI(I) and EA2 and to separate contacts EAS and EAL Contacts EAI(I) are in the circuit for the neutralizing coil of relay SM(I) of the stopping magnet, the advance having progressed suiiiciently by this time for the brushes to be o the stationary contacts for the iloor at which the car is positioned. Contacts EA2 further prepare the circuit for the coil of automatic return relay XH. The separation of contacts EAS prevents energization of the direction switches once the advancer mechanism has been energized to advance the carriage. Contacts EAl prevent re' operation of the stopping magnet once a call has been picked up after the car' has come to a stop at the floor for which the call is registered. This is especially useful in cases where the advancer mechanism advances the brushes into engagement with their stationary contacts for the iloor beyond before starting of the car takes place, as, for example, in the system of the Waters and Glaser patent previously referred to.

The advance takes place fairly rapidly so that, upon the closure of the hatchway door and car gate, a circuit is established for the coil of fleid and brake switch H through contacts SSI, PUB, up limit switch |00, gate contacts G, door contacts DL, start control switch contacts I01 and safety switch IIO.

Switch H upon operation engages contacts H2, H3, H4, H5, H6, H1, H8 and H9 and separates contacts HI and HIO. The separation of contacts HI prevents operation of the direction switches during operation of the car. Contacts H2 by-pass start control switch contacts |05 in the advancer motor circuit. Contacts H3 complete the circuit for the coil of operating switch sequence relay OS. 'I'he operation of operating switch sequence relay OS causesv the engagement of contacts OS2 and separates contacts OSI. The purpose of contacts OSI will be explained later. The engagement of contacts OS2 completes a holding circuit for the C011 of auxiliary stopping relay ASM. Contacts Hl by-pass start control switch contacts I 01, establishing a selfholding circuit for the coil of switch H. Thus with its contacts all by-passed, .the start control switch may be returned to oi! position. Contacts H5 further prepare the circuit for the coil of speed switch E. Contacts H0 and H1 complete the circuit for brake release coil BR, while contacts H0 and H9 complete the `circuit for the generator field winding 98. Contacts HIO disconnect the generator eid winding from across the generator armature. The completion of the circuit for the generator separately excited field winding causes current to be supplied from the generator armature 95 to the hoisting motor armature 98 and, the brake being released as a result of the energization of its release coil BR, the elevator motor starts the car in the up direction.

The brake, upon being released, effects the separation of contacts BRI, which act to remove the short circuit for the coil of brake resistance relay BK. This relay operates to separate its contacts BK2 to insert cooling resistance |03 in circuit with brake release coil BR. It also engages contacts BKI, which completes the circuit for the coil of speed switch E through contacts H5, SS2, PU9, up limit switch I II and safety switch IIO. Switch E upon operation engages contacts EI to short-circuit a portion of resistance IOI in the circuit of the generator field winding 96. This applies full voltage to the generator separately excited field winding, causing the generator voltage to build up to full value to bring the elevator car up to full speed.

It will be assumed for the present that no push buttons have been pressed. Service switches I2I and II3 are closed under the conditions where cars 3' and 4 serve only outgoing calls from floors in the lower zone, i. e., floors 2, 3 and 4. Switches IISG) and II3(4) connect the coils of zone switches ZS(3) and ZSUI) for elevators Nos. 3 and 4 respectively to the feed lines. This causes contacts ZS2(3) and ZS2(4) to be in engagement and contacts ZSI(9), ZSIUI), ZS3(3) and ZS3(4) to be in separated condition. As brush 10(I) of elevator No. 1 moves upwardly and engages stationary contacts 12(I), 13(I) and 14H) for the second, third and fourth floors,

highest down hall call relay XSD is energized as each successive engagement occurs. The circuit completed by the engagement of the brush with contact 12( I), for example, 1s through service switch |20, contacts ZS2(3) and ZS2(4) in parallel and contacts 4D2 and 3D2 of the down fourth and third vfloor' relays. Relay XSD.

upon operation separates contacts XSDI (I) and engages contacts XSD2. Contacts XSD2 are in -the circuit for the coil of automatic'return relay XH, this circuit being open, however, at contacts XC2. Contacts XSDIU) are in the circuit for the coil of relay XC( I) this coil being maintained energized, however, from line by wire II2(I), switchv I2I(I) and hook switches 85H) and 06(I) for the fth and sixth floors.

Upon the engagement of brush 18( I) with iifth iloor stationary contact 1I5(I) to reestablish the circuit for the coil of relay XSD(I), in this case through contacts 1D2 and 0D2, cam 08H) engages and opens .iifth iioor hook switch 85H) which, together with the separation of contacts XSDI (I) breaks the circuit for the coil of highest car call relay XC( I This relay; upon dropping out, reengages contacts XCI(I) and X02.

The engagement of contacts XCIU) completes 75v tacts ASM2( I) a circuit for the coil of highest up hall call relay XSUU) through contacts 6U2 and 5U2 oi the sixth and :fifth iioor up floor relays, stationary contacts 35H) and brush 68(I). Relay XSUU) upon operation engages contacts XSUI which, together with the engagement of contacts XC2 and KSDZ, completes a circuit for the coil of automatic return relay XH.

Automatic return relay XH upon operation engages contacts XHHI), XH2 and XHt and separates contacts XHS. The engagement of contacts XH2 establishes a holding circuit for the coil of relay XH by-passing contacts XC2, XSD2, XSUE, ASMS and EA2. Contacts XH4 prepare a circuit for the operating coil of down direction switch PD and the reset' coil of up direction switch PU. Contacts XH3 break the circuit for the coil of auxiliary direction relay PR, causing this relay to drop out. Relay PR separates contacts PREM) and reengages contacts PRI(I), rendering brush 48H) effective and brush 58(I) ineiective. The engagement of contacts XHI (I) completes a circuit through contacts EAI (I) and SMHI) for the neutralizing coil SMH) of the stopping magnet. This coil acts to oppose the operating coil of magnet SM, releasing the pawls and causing the separation of contacts SM|(I), SM2 and SMS. Contacts SMi I) and SMS break the energizing circuits for the coils of the stopping magnet, while contacts SM2 break the circuit for the coil of the auxiliary stopping switch ASM and one coil of auxiliary speed relay EA. The auxiliary stopping switch separates contacts ASMI (l), ASM3 and ASMI and reengages con- Contacts ASMI (I) disconnect brush 38( I) from line Contacts ASM2 shortcircuit neutralizing coil SM(I) of the stopping magnet. Contacts ASM3 are by-passed by contacts ICE-I2 in the circuit for the coil of automatic return relay mi. Contacts ASM4 deenergize the advancer motor AM. Relay EA does not drop out on deenergization oi its coil in series with the coil of switch ASM, being held in operated condition by its coil in parallel with the coil of speed switch E.

As the car continues its upward travel, the upY pawl engages the fifth floor stopping collar, causing the opening of selector switches SS2 and SSI in sequence. 'Ihe opening of switch SS2 breaks the circuit for the coil of speed switch E, which drops out, separating contacts EI to reinsert resistance IUI in the circuit of the generator iield winding. This decreases the voltage of the generator, causing the car to slow down. The opening of switch SS2 also breaks the circuit for the other coil of relay EA, which drops out to separate contacts EAI(I) and EA2 and to reengage contacts EA3 and EA4. Contacts EAI( I) are in the circuit for the neutralizing coil of the stopping magnet already broken at contacts SMI (I). Contacts EA2 are by-passed by contacts XH2. Contacts EA3 further prepare the circuit for the operating coil of down direction switch PD and the reset coil of up direction switch PU. C ontacts EAG are in the initial energizing circuit of the operating coil of stopping magnet SM, this circuit being open at contacts SMI( I).

The opening of switch SSI, which occurs as the car arrives at the landing, breaks the circuit for the coil of eld and brake switch H. Switch H, upon dropping out, separates contacts H2, H3, H4, H5, HB, H'I, H8 and H9 and reengages contacts HI and HID. Contacts H2 are in the circuit for the advancer motor AM, which was previously deenergized. Contacts H3, H4 and H5 are in the circuits i'or the operating coils of magnet SM and switches H and E, which circuits have aleady been broken. The separation oi contacts HB and Hl' deenergizes brake release coil BR and the separation of contacts H8 and `H$ disconnects the generator separately excited field winding 96 from the feed lines. Thus the external excitation of the generator is discontinued and the brake is applied to bring thecar to a stop at the iifth floor landing. The engagement of contacts HIB reconnects the separately excited field winding across the generator armature substantially `to destroy the residual iiux of the generator field.

The separation oi.' contacts H6 and H1 also breaks the circuit for the coil of brake resistance relay BK which drops out to separate contacts BKI and reengage contacts BK2. Contacts BKI are in the circuit for the coil of speed switch E, which circuit has already been broken. Contacts BKZ short-circuit cooling resistance ID3 for the brake release coil in preparation for the next starting operation. The separation oi' contacts H3 also breaks the circuit for the coil of operating switch sequence relay OS, provided the start control switch has been returned to neutral position. However, if the start control switch is held in position where contacts IUE are bridged, switch OS remains energized upon the separation of contacts H3 so that contacts OSI remain separated to prevent the reoperation of stopping switch SM. This prevents a restarting operation unless the start control switch is returned to neutral.

'I'he reengagement oi contacts H I completes a circuit through contacts PDS, XH4 and EA3 for the operating coil of the down direction switch PD and reset coil of the up direction switch PU. This causes the reset of the up direction switch to separate contacts PUI (I), PU2(I), PU3, PUI, PU5, PUT, PUB, PU9, PUI Il and PUII and the reengagement of contacts PUE. It also causes the operation and latching oi' the down direction switch to engage contacts PDS, PDT, PDB, PDS, PDIO and PDII and to separate contacts PDG. The separation of contacts PUIU and PUII and the engagement of contacts PDII) and PDII prepares the circuit for the generator field winding for downward car travel. The separation of contacts PUI(I) and PU2( I) renders brushes 68(I) and 18( I) ineffective for downward travel. The separation of contacts PU3 deenergizes the coil of automatic return relay XH and prevents operation of this relay during downward car travel. The engagement of contacts PUB prepares the circuit for automatic reoperation of the direction switches to restore the circuits for upward car travel when the car reaches the lower terminal iloor. The separation of contacts PU5 and the engagement of contacts PDE causes the deenergization and reenergization of the car button magnet CBM. 'I'he separation of contacts PUI and engagement oi contacts PDT connect the advancer motor circuits for advancing the carriage in the down direction. The separation of contacts PU8 and the engagement of contacts PDB transfer the circuit for the coil oi' switch H so as to be subject to lower terminal limit switch I I6 while the separation oi' contacts PUB and the engagement of contacts PDS transfer the circuit for the coils of speed switch E and relay EA so as to be subject to lower terminal limit switch IIl. These parallel circuits are provided to insure the deenergization of these switches at the terminal landings while permitting their reenergization described, there were any up hall buttons or car buttons pressed for floors above the eifective posh tion of the car, the car would be caused to stop at the floors for which the push buttons are provided. Assume, for example, that two passengers entered the car at the first door, one desiring to be carried to the third floor and the other to the sixth floor. Upon the passengers having announced their destinations, the car attendant presses car buttons C3( I) and C8(I) for the third and sixth floors, these buttons when released being held in operated condition by the car button magnet CBM. Upon the engagement oi brush 38H) with stationary contact 33H), a circuit is completed for neutralizing coil SMU) of the stopping magnet. This causes the car to be slowed down and brought to a stop at the third door in the manner previously described. However, as the highest car call relay XC is maintained energized during this operation, automatic return relay XH is not operated so that the car remains set for upward travel. Thus, upon reoperation of the start control switch after the passenger transfer at the third iloor has been effected, the ,door and gate close and the car starts in the up direction. Highest down hall call relay XSD(I) operates as before as brush I8(I) engages its contacts for floors 2, 3, 4 and 5. However, automatic return relay XH is not operated as brush v18(I) engages the fifth oor contact, owing to the fact that the highest car call relay XC(I) is maintained operated through the sixth floor car button C6(I) at the time contacts XSDI(I) separate. Upon the engagement of brush 'I8(I) with sixth floor stationary contact 16(I) to effect separation of contacts XSDI(I), the six'th floor hook switch 88H) is opened by cam 88H) so that relay XC( I) is deenergized, causing the operation of automatic return relay XH. This relay engages contacts XHI(I) to complete the circuit for neutralizing coil SM(I) and thus effect the reset of stopping magnet SM, this circuit also being completed by the ,engagement of brush 38H) with stationary contact 36. The reset of the stopping magnet causes the car to be slowed down and brought to a stop at the sixth oor. Contacts XH4 being in engagement under the assumed conditions, the car is set for the opposite direction of car travel upon the reengagement of contacts HI. The separation of contacts PU5 and engagement of contacts PDS incident to setting the car for downward travel causes the momentary deenergization of car button magnet CBM to release operated car buttons C3(I) and CIi(I)/.4

Similar operation is had4 in case an up hall button is pressed. Assume, for example, that the up hall button U2 at the second iloor is pressed before brush 58( I) engages contact 52( I). When such engagement takes place, a circuit is completed from line through restoring coil 2U and contacts 2UI of the up second i'ioor relay, second floor stationary contact 52H), brush 58H), contacts PR2(| and by way of cross wire I8(I) through contacts NSI(I), EAI(I) vand SMIU) and coil SMU) to line This causes the resetting of the stopping switch SM, causing thevcar to be slowed down and brought to a stop at the second floor. The reengagement of contacts ASM2(I) upon the dropping out of switch \ASM short-circuits coil SMU), increasing the current supplied to the restoring coil 2U of the up second iloor relay, causing this relay to be reset. As relay XC is maintained operated under l the assumed conditions, the car remains set for upward travel. IIThe car, upon being restarted in the up direction, continues at least to the fifth oor or farther in case the passenger taken on at the second floor desires .to be carried to a floor above the iiith floor.

If the car is traveling in the up direction and the only button pressed is the up hall button U5 at the .fifth floor, automatic return relay XH is not operated as the car arrives at the fifth floor. 'I'he fth oor relay when in operated condition maintains contacts 5U2 separated in the highest up hall call circuit, thereby preventing the operation of highest up hall call relay XSU upon the engagement of brush 68(I) with contact 65H) and the engagement of contacts XCI (I) as a result of the operation of relay XSD as the car approaches the fifth floor. Aspreviously explained, the floor relay is not reset until after the reset of the stopping magnet SM as the up hall call at the fifth floor is picked up, due to the fact that the current supplied to the restoring coil of relay 5U is not sufliclent to reset the relay until after theA engagement of contacts ASM2( I). 'I'herefore contacts ASM3 in the circuit for the coil of automatic return relay XH separate before contacts 5U2 reengage, thereby preventing the `completion of the circuit for the coil of relay XH upon the operation of highest up hall call relay XSU to engage contacts XSUI as a result of the reengagement of contacts 5U2. .Thusthe car is maintained set for upward travel so that the passenger taken on at the fth iloor may be taken to his destination before automatic reversal of the direction of car travel is effected.

Ii' the car is travelling in the up direction and the'only button pressed is the down hall button D6 at the sixth floor, automatic return relay XH is not operated as the car approaches the ilfth floor owing to the fact that the separation of contacts 8D! in the highest down call circuit prevents the operation of the highest down call relay XSD(I) upon engagement of brush 18(I) with the iifth floor stationary contact 15(I). As the car approaches the sixth floor, the engagement of brush I8(I) with sixth oor stationary contact 16(I) completes the circuit for the coil of relay XSD( I). This relay operates as previously described to cause the .deenergization of highest car call relay XC(I) and thus the operation of highest up hall call relay XSU(I thereby effecting the energization of the coil of automatic return relay XH to cause the car to be set for downward travel as it arrives at the sixth floor. The automatic return relay upon operationy engages contacts XHI(I), causing the stopping magnet SM to be reset, thereby causing the car to be slowed down and brought to a stop at the sixth iioor. It also separates contacts XH3 to deenergize auxiliary direction relay PR. Relay PR separates contacts PR2(I), rendering brush 58H) ineffective. It also engages contacts PRI( I), rendering brush 48( I) effective. 'Ihis completes a circuit through sixth oor stationary contact I6(I) for kthe restoring coil of the down sixth oor relay 6D, causing this relay to be reset.

If the down sixth floor relay and the up sixth floor relay are both operated, the separation of contacts 6U2 in the highest up hall call circuits prevents the operation of highest up hall call relay XSUU) and thus prevents the operation of automatic return relay XH to set the car for iownward travel upon its being brought to a stop t the sixth floor. Furthermore, as relay XH is not operated, contacts XH3 remain separated, preventing the reset of the down floor relay for the sixth floor by the engagement of brush 48( I) with contact 46M).

Once the car set for upward travel has set up circuits to cause the direction of car travel to be changed tor down upon the car being brought to a stop at a floor, that is, once the circuit for the coil of its automatic return relay XH has been completed, the registration of a call for a floor above that floor or of an up hall call for that floor after the establishment of this circuit is ineffective to prevent operation of the direction controlling switches to set the car for downward travel as it comes to a stop. This is due to the fact that contacts XC2, XSD2 and XSU are all by-passed by the holding contacts XH2 of the automatic return relay. Any such call registered by a hall button remains operated under such conditions so that this call is ultimately responded to. This will be understood from later description.

It is believed that it will be seen from the above description that car No. 1, once started in the up direction, continues to travel in the up direction at least until a certain floor (the fifth floor in the arrangement illustrated) is reached, stopping at that floor if no call is registered for any floor above and continuing past that floor without stopping if neither a car call nor an up hall call is registered for that floor and a call is registered for a floor above. In the latter event, the car continues to travel in the up direction until it reaches the floor for which the highest call, either car call or down hall call or both, is registered, before reversal becomes effective. In case the highest call is an up hall call, the car remains set for upward travel in order that the intending passenger may be taken in the indicated direction. During its travel in the up direction, stops are made in response to calls registered by car buttons for floors intervening the lower terminal and its ultimate destination, and also in response to up hall calls for such intervening floors. The stops are made in the order of succession of floors, regardless of the order in which the calls are registered. Stops are not made at intervening floors in response to down hall buttons because the automatic return relay XH is not operated under such conditions.

During downward travel of the car, stops are made in response to all car calls and down hall calls that are registered. Up hall calls, however, are answered only by an up travelling car. It is believed that the stops in response to car buttons will be understood from the previous description inasmuch as when a car button is pressed it is maintained operated by they car button magnet CBM so that, upon the engagement of brush 38(l) with the contact rendered alive by this button, the call is picked up and the car is caused to slow down and come to a stop at the floor. Similarly, each down hall button that is pressed operates a down floor relay that remains operated until the contact rendered alive thereby is engaged by brush 48(I) to pick up the call. This causes the stopping magnet to drop out, the floor.

relay to be reset and the car to be slowed down and brought to a stop at the floor at which the button is located. The stops are made in the order of succession of iloors regardless of the order in which the calls are registered. When the car becomes iilled to capacity the non-stop button NSB( I) is pressed, deenergizing the non-stop relay NSU). This relay drops out to separate its contacts NSHI), rendering brush 48(1) in effective to pick up further down calls during the remainder of its trip to the lower terminal. Car buttons, however, are responded to unaffected by the non-stop button, so that stops may be made to discharge passengers.

The operation of elevator No. 2 is the same as that o'f elevator No. l, previously described. If both cars are set for travel in the up direction, both will travel at least to the fth floor before reversing. Each car Will continue beyond the fifth floor if a car button is pressed in that car for a floor above, an up hall call is registered for the fifth floor or a hall call is registered for a floor above. With both cars set for upward travel, each up hall call is answered by the car whose brush 58 is the first to engage its stationary Contact for the floor for which the call is registered. The highest down call for a floor above the fth floor is answered by the rst car whose brush 18 engages its stationary contact for that floor. If only one hall call remains to be responded to for a floor above the fth floor, upon its being picked up by one of the cars, the other car, if it is in effect below the fifth floor, is caused to travel at least to the iifth floor and to stop thereat and become set for downward travel if no car button in that car is pressed for a floor above. If such other car is in effect above the fifth floor at the time the hall call is picked up, the -car is automatically caused to slowdown and stop at the floor the stationary contact for which is next to be engaged by brush 18 for that car after the reset of the floor relay, or if in engagement with a contact at that time at the floor for which the contact is provided. For example, assume that both cars are set for travel in the up direction and that the only call registered is a hall call at the seventh floor. Upon the engagement of brush 58 for one of the cars, say car No. 1, with its contact 51(I) for the top floor, the stopping magnet for that car is deenergized, which causes the reset of the seventh floor relay in the manner previously described, the circuit being through brush 58(I Assume that the next stationary contact engaged by brush 18(2) for car No. 2 after the reset of the seventh floor relay' is the sixth floor contact 16(2). As this engagement takes place, relay XSD(2) is operated, causing the operation of relay XH for car No. 2 and the car to be slowed down and brought to a stop at the sixth floor and set for travel in the down direction. If the hall call registered had been an up call at the sixth floor and this call had been picked up by car No. l, car No. 2 would be caused to slow down and stop at the fifth floor in response to the engagement of brush 18(2) with contact 15(2). This is due to the fact that the reset of the up sixth floor relay to reengage contacts 6U2 permits the operation of highest up hall call relay XSU(2) in response to the reengagement of contacts XCI(2) as a result of the operation of relay XSD(2). Thus relay XH for car No. 2 is operated, causing the car to be slowed down and brought to a stop at the fifth floor, and set for travel in the down direction.

If more than one hall call remains to be responded to for a floor above the iifth floor and the farthest one of these calls is picked up by one of the cars, the other car is caused to continue to travel in the up direction to answer this call at an intervening floor.

As for elevators Nos. 3 and 4, due to the fact that relays ZS for these cars are operated under the assumed conditions, their cars do not serve floors above the fourth floor. Taking car No. 3, for example, owing to the fact that contacts ZSI(3) are separated, car buttons for oors above the fourth oor and service switch |2I (3) are rendered ineffective. Thus highest car call relay XC(3) is not energized through the hook switches for the second,.third and fourth floors unless the car button for one of these oors is operated. Highest down hall call relay XSD(3) is not subject to down floor relays for iloors above the fourth iloor owing to the fact that contacts ZS3(3) are separated. The car cannot respond to up hall calls owing to the fact that contacts ZS4(3) and PR3(3) are separated, deenergizing coil NSG) of elevator No. 3 non-stop relay. Thus contacts NS|(3) are separated, rendering brush 58(3) ineiective when the car is set for upward travel, this brush being ineffective when the car is set for downward travel due to the fact 'that contacts PR2(3) are separated. Also, contacts NS2 for elevator No. 3 are engaged, by-passing contacts XSD2, XSUI, ASM3 and EA2 for elevator No. 3, so that the circuit for the coil of the automatic return relay for elevator No. 3 is coml pleted upon engagement of contacts XC2 for elevator No. 3.

If the starting of car No. 3 in the up direction is initiated under conditions where no car calls for that car for the second, third or fourth iioors and no down hall calls for the second, third or fourth floors are registered upon the engagement of brush 18(3) with contacts 12(3) highest down hall call relay XSD(3) for car No. 3 is operated, causing the deenergization of highest car call relay XC(3). This completes a vcircuit for automatic return relay XH for car No. 3, causing the car to be slowed down and brought to a stop at the second floor and set for travel in the down direction. However, ii' a down hall call had been registered for say the third floor, relay XSD(3) is not operated upon the engagement of contacts 18(3) with contacts 12(3), the completion of this circuit being delayed until the brush engages contacts 13(3), whereupon relay XC(3) is deenergized as before, causing the operation of automatic return relay for elevator No. 3 to cause the car to be slowed down and brought to a stop at the third iioor, and set for travel in the down direction. If a down hall button had been registered for the fourth floor as well as the third floor, the energization of relay XSD(3) is delayed until the engagement of brush 18(3) with contacts 14(3) and the car passes the third oor without stopping. 'Ihe car is slowed down and brought to a stop at the fourth floor in response to the engagement of brush 18(3) with contacts 14(3) and set for travel in the down direction. If

Ithe only down hall call registered is a down call at the second floor, relay XSD(3) is energized upon engagement of brush 18(3) with contacts 12(3). In each case the down floor relay is reset in response to the deenergization of auxiliary direction relay PR(3) for elevator No. 3 as a result of the operation of automatic return relay XH for elevator No. 3. Upon being deenergized, relay PR(3) engages contacts PRI (3) in the circuit for brush 48(3) and engages contacts PR3(3) to effect the energization of relay NS(3) which engages contacts NS|(3) completing the reset circuit.

If a second, third or fourth oor car button in elevator No. 3 had been pressed it would maintain relay XC(3) operated until the corresponding hook switch is engaged and opened by cam 88(3), thus preventing the car being set for the opposite direction of c ar travel at a lower floor. In other words, if the fourth floor car button, for example, had been pressed, relay XC(3) is not deenergized until the engagement of hook switch 84(3) by cam 88(3). However, if the second and third floor car buttons also were pressed, the car stops at the second and third floors as well as the fourth iioor in response to the car buttons for these oors, the calls being picked up by the engagement of brush 38(3) with the contacts 32(3) and 33(3) respectively.

It will be seen from the above description that car No. 3, when started in the up direction, continues to travel in the up direction until it reaches the highest floor in its zone for which a down hall call is registered or a car call for that car is registered. During its travel in the up direction, stops are made in response to car buttons pressed for floors intervening the lower terminal and its ultimate destination. Stops are made in the order of succession of floors regardless of the order in which the calls are registered. No stops are made in response to up hall calls, these calls being answered by car No. 1 or car No. 2. If. upon the starting of car No. 3 in the up direction being initiated, no car calls or down hall calls are registered before the engagement of brush 18(3) with contact 12(3) and the opening of hook switch 82(3), the car is automatically caused to slow down and stop at the second oor and becomes set for travel in the down direction upon the stop being made.

During downward travel of the car, stops are made in response to all car calls and all down hall calls that are registered. As in the case of elevators Nos. 1 and 2, when a car button in car No.4 3 is operated it is maintained energized by the car button magnet so that upon the engagement of brush 38(3) with the contact rendered alive" by this button, the call is picked up and the car is caused to slow down and come to a stop at the floor. Also, when brush 48(3) engages a contact rendered alive" by an operated down oor relay, the call is picked up and the car is caused to slow down and come to a stop at the floor for which the contact is provided. The stops are made in the order of succession of oors regardless of -the order in which the calls are registered.

The operation of elevator No. 4 is the same as that of elevator No. 3, previously described. If both of these cars are set for travel in the up direction, a down hall button is pressed for a. oor in the lower zone and no car or down hall buttons for oors in the lower zone above that oor are pressed, this call is answered by the car whose brush 18 is the first to engage a stationary contact for the floor for which the call is registered. The other car, if no car buttons in that car or down hall buttons for intervening oors' are pressed, is automatically caused to slow down and stop at the floor the stationary contact for which is rst to be engaged by brush 18 for that car after the reset of the iloor relay. However, if a down hall call, for example, is registered for an intervening iloor, this other car is caused to continue its travel in the up direction and come to a stop at the floor for which the call is registered.

Both cars Nos. 3 and 4 answer down hall calls for floors below when set for downward travel, the car which answers each call being the one whose brush 48 rst engages the stationary contact for the floor for which the call is registered. Inasmuch as the circuit arrangements enable cars Nos. 1 and 2 to answer down calls at all ioors when these cars are set for downward travel, these cars may assist cars Nos. 3 and f1 in answering down calls in the lower zone. How-` ever, when cars Nos. 1 and 2 become filled, the attendantsA may prevent their picking up further down calls in their downward travel by pressing the non-stop buttons' NSB in the respective cars. The pressing oi this button in car No. 1, for example, causes the deenergization of the non-stop relay'NS (l) which, upon dropping out, separates its contacts NSHl) to render brush 48H) ineffective. So long as the non-stop button in car No. 1 is held depressed, this car is unable to pick up any down hall calls in its downward travel. The down oor relays are not reset so that these calls are picked up by the next car set for travel in the down direction whose alive brush 48 engages the stationary contacts for the floors for which the calls are registered. Cars Nos. 3 and 4. may be similarly non-stopped by their attendants pressing the non-stop buttons NSB in the respective cars.

Elevator systems operating in the manner above described are especially suitable for such buildings as oiiice buildings, where there is a large amount of outgoing traiiic concentrated at a certain time in the evening. In such buildings, the quitting time is the same for most employees, which creates a sudden maximum demand for elevators to depopulate the building. Inasmuch as there is very little or no inter-iloor trafc at such time, each elevator car runs express from the lower terminal to the highest down call in its zone, where it is brought to a stop and set for travel in the down direction. The car then proceeds to pick up down calls on its downward trip until filled to its maximum capacity. The car is then expressed (by pushing the non-stop button) to the lower terminal, where the passengers are discharged, whereupon it is immediately started on its upward trip for more passengers. Inasmuch as the elevators are assigned to clenite zones, equal service to each portion of the building is assured. Furthermore, owing to the iact that the cars serving the upper zone may, if not loaded to capacity, make stops in response to down hall calls inthe lower zone to assist the lower zone cars in depopulating that portion of the building, the entire handling capacity of the elevator system is utilized. Thus the building is depopulated in a minimum of time while assuring equalized service to all floors.

At certain times it may be desirable to cause another elevator car toassist cars 1 and 2 in serving the upper zone or to take the place of one of these cars when it is temporarily out of service. This may be done in the case of elevator No. 3, for example, by opening service switch Ii3(3), deenergizing elevator No. 3 zone switch ZS. This switch upon dropping out reengages contacts ZSI (3) ZS3(3) and ZS4(3) and separates contacts ZS2(3). The engagement of contacts ZSI(3) renders service switch |2I(3) effective to cause the car to travel at least to the fifth floor before becoming set for travel in the down direction. The engagement of these contacts also renders the car buttons for the fth, sixth and seventh loors in car No. 3 eective to control that car. The engagement of contacts Z840) causes the non-stop relay NSG) for elevator No. 3 to be energized when the car is set for upward travel, thus enabling this car to stop and pick up up calls when set for travel in the up direction. The car responds to the highest down call the same as described for elevators Nos. 1 and 2. The control circuits for car No. 4 may be similarly changed over to cause this car to serve the upper zone by opening service switch l l3(4).

The elevators may also be changed over to operation whereby each car set for up travel is automatically set for travel in the down direction upon being brought to a stop at a :door when, at the time that circuits are set up to cause the car to slow down and be brought to a stop at that floor, no push buttons are pressed which require or indicate further travel in the up direction from that floor. This may be done by opening service switches l|3(3) and ll3(4) for elevators Nos. 3 and 4 and by throwing over service switch I2! for each elevator from the lower position shown to its upper position to render control of the highest car call relay XC for each car subject to the fth oor car button in that car as well as the other car buttons. Under such conditions, as both contacts ZS2(3) and ZSZM) are separated and both contacts ZS3(3) and ZS3(4) are engaged, the highest down hall call relay XSD for each car is not energized until brush 18 for that car engages a stationary contact under conditions where no.

down hall calls are registered for oors above the one at which the stationary contact is provided. If no car call is registered in that car for a iioorv above that oor, the operation of relay XSD causes the deenergization of the highest car call relay XC for that car; If no up hall call is registered for that iioor or for a floor above, this causes the operation of the highest up hall call relay XSU for that car and consequent operation of the automatic return relay XH for that car, causing the car to be slowed down and brought to a stop at the floor and set for downward travel. If a car call is registered for a floor above, the highest car call relay XC is not deenergized so that a stop is not made in response to the down call. Relay XC is maintained operated until the hook switch for the iioor for which the highest car call is registered is opened and if at that time no further hall calls have been registered which require or indicate further travel in the up direction, relay XH is energized to cause the car to be slowed down and brought to a stop at the floor and the setting of the car for travel in the down direction. If an up hall call is registered, this causes the car to be brought to a stop at the floor for which the call is registered and to be maintained set for upward travel so as to be restarted away from that oor in the up direction. Upon becoming set for downward travel, each car stops in response to calls registered by its car buttons for floors below and also in response to down hall calls for oors below.

This operation is particularly suitable for the morning peak in buildings such as cnice buildings, Where there is a large amount of incoming traiic concentrated at a certain time in the morning. Inasmuch as working hours in such a building begin at the same time for the majority of employees, this creates a maximum demand buttons. Assuming no Ihall calls, each car au-` tomatically becomes set for travel in the down direction at the door at which vthe last stop is made to discharge a passenger, runs express to .the ground floor, takes on more passengers and the cycle is repeated. vThus each car provides ak maximum of transportation 'capacity with minimum car travel to meet the demands placed' upon the system.,

These operations are also suitable for noon peaks. At the noon hour, when there is a severe demand for service to depopulate the building. the same operation as forthe evening peak may be provided. That is, switches ||3(3) and ||3(4) are closed and all of switches |2| are placed in their lower positions automatically assigning the cars to -their zones to provide zone return operation, causing elevators Nos. 3 and 4 to serve the lower zone and elevators Nos. 1l and 2 to run to the upper zone before becoming set for downward travel. Just before one oclock, when there is a severe demand for service to take the employees back into the building, the same operation as for morning peak may be provided. That is, switches IISG) and ||3(4) are both opened and all ot switches |2l are thrown to their upper positions to provide highest call return" operation, causing each car to become set for travel in the down direction upon making a stop at a floor in its upward travel under conditions where no calls are registered which require or indicate further travel in the up direction.

During periods intermediate the morning and noon peaks and the noon and evening peaks, the elevators may b'e caused to always run to the upper terminal before reversing. This may be eiected by opening service switch |24 for each) elevator, preventing the operation of relay XH and thus preventing the automatic setting of the car for downward travel until the engagement of brush 90 with contact 9| as the car arrives at the upper terminal and contacts HI reengage. Also, service switch in the circuit common to the highest hall call circuits is opened to prevent the energization of the coils of any of the XSU or XSD switches duringgsuch intermediate periods. Service switches H3 for elevators Nos. 3 and 4 are both opened to deenergize zone switches ZS for these elevators, thus rendering the car buttons in cars Nos. 3 and 4 for the fifth, sixth and seventh oors effective to control cars Nos. 3 and 4, as in the case of elevators Nos. 1 and 2. With the service switches in these positions, each elevator, when travelling in the up direction, stops in response to its car buttons which are pressed and also in response to unanswered up hall calls which are picked up. No stops are made during its upward travel in response to'down hall calls. When set for travel in the down direction, each car stops in response to its car buttons which are pressed and also in response to unanswered down hall calls which are picked up. No stops are made during downward travel in response to up hall calls.

Scheduling mechanism may be employed for the elevators if desired on terminal to terminal operation. This mechanism may cause the giving of starting signals to start .the cars away from the terminals at timed intervals, thereby effecting operation of the cars so as to give emcient service to all floors of the building. Scheduling mechanism such as shown in the patent to David C. Larson No. 1,966,071, granted July 10, 1934, may be employed if desired. Scheduling mechanism may be used also when the cars are under highest call return operation to automatically give the starting signal to the cars only at the lower terminal. When the direction of travel of the car has been changed upon a stop being made in the upward travel of the car, the attendant is notiiied by the extinguishing of lamp in the car. Scheduling mechanism may also be used when the cars are under zone return operation,

the starting signalvbeing given to each elevator as it arrives at the lower terminal so that it will,

immediately start in the up direction after discharge of its passengers.

The above 'system' may also be employed for night service. Any one or more of the cars may be picked out for use during this period. It is preferredv to operate highest call return for night service, with a signal to advise the attendant in the car when a call is registered.

Although not described, it is to be understood that hall lanterns are provided for the various cars at the landings. These lanterns may be controlled as disclosed in the aforementioned patent to Waters and Glaser with those at the first floor also controlledby the dispatching and scheduling mechanism so that the hall lantern for a car is lighted only in the event that it is about to leave the floor, thereby advising the intending passenger at that floor which car to take. For zone return operation, electric signs may be employed to direct any intending passengers at the ground oor to the cars serving the upperv zone.

Although the invention khas. been described as applied to an installation in which each zone is served by two cars, it is to be understood that it is applicable to installations in which the zones are served by other numbers of cars. The control circuits for each zone are the same for each car serving that zone.` It is also to be understood that the number of iloors in each zone may be varied, the circuits being arranged in accordance with the number of floors. The floor constituting the lower terminal in an upper z'one (the fifth floor in the circuits shown) is determined by the hook switch connected tothe feed line by switch I2| and the stationary contact to which contacts ZS2 and ZS3 are connected, the car buttons controlled by contacts ZSI being governed accordingly. Thus, for example, the upper zone lower terminal in the Vcircuits shown may be changed from the fifth to the sixth iloor by connecting switches |2| to hook switches 86 instead of hook switches 85, by connecting the circuit constrolled by contacts ZSZ and ZS3 to contacts 15 and 6D! instead of to contacts 14 and 5D2 and by connecting the fifth floor car buttons C5(3) and 05(4) directly to feed line -linstead of subject to ZS contacts. y

If desired, the circuits may be arranged to cause each car when travelling in the up direction on zone return operation always to travel at least to some intermediate floor in its zone regardless of whether any call is registered to which that car is responsive for a floor above the lowest iloor in that zone. This may bedone. for example, in the circuits illustrated, assuming that it is desired to have cars Nos. 1 and 2 always travel at least to the sixth floor instead of the fifth oor and that it is desired to have cars Nos.

3 and 4 travel at least to the third oor instead of the second floor, by connecting the sixth floor hook switch 86 of each of the four elevators instead of hook switch 85 directly to feed line through switches |21 and by providing a similar circuit connecting the third iloor hook switch 83 of each elevator directly to feed line through a similar service switch. Also, the sixth and third oor car buttons are disconnected from their respective hook switches. The fifth oor car buttons, however, are connected to their corresponding hook switches. With this arrangement, cars Nos. 1 and 2, when setfor travel in the up direction, travel at least to the sixth floor and cars Nos. 3 and 4, when set for travel in the up direction, travel at least to the third floor regardless of the calls registered. However, cars Nos. 3 and 4 do not answer calls above the fourth floor as the circuits controlled by the contacts of zone switches ZS are not changed.

It is to be further understood that, although the invention has been described as applied to two zones, any number of zones may be provided, depending upon the requirements of the particular installation. This may be done by carrying forward the principles already set forth. To provide for example a zone intermediate the upper and lower zones previously described, assuming for convenience a larger number of floors, say fifteen, and two more elevators, with elevators Nos. 1 and 2 being `assigned to oors 11 to 15, elevators Nos. 3 and 4 being assigned to floors 6 to 10 and elevators Nos. 5 and 6 being assigned to floors 2 to 5; the hook switches for the eleventh fioor for elevators Nos. 1, 2, 3 and 4 would be connected to line through service switches as is done for hook switches 85 in Figure 2, and the hook switches for the sixth floor for elevators Nos. 3, 4, 5 and 6 would be connected to line through service switches as is done for hook switches 85 in Figure 2; zone switches for elevators Nos. 3, 4, 5 and 6 would control the car buttons for those cars for floors 11 to 15 in the same manner as those for floors 5 to '7 are controlled for cars Nos. 3 and 4 in Figure 2 and would control the rendering of the circuits for the coils of relays XSD subject to down hall calls for floors above the tenth floor in the same manner as the rendering of the circuits for these coils subject to down hall calls for floors above the fourth oor is controlled by the zone switches in Figure 2; and additional zone switches for elevators Nos. 5 and 6 would control the car buttons for those cars for floors 6 to 10 in the same manner as those for floors 5 to '7 are controlled by the zone switches of cars Nos. 3 and 4 in Figure 2 and would control the rendering of the circuits for the coils of the relays XSD subject to down hall calls for the sixth to the tenth iioors in the same manner as this is effected for elevators Nos. 3 and 4 for floors above the fourth floor in Figure 2. This arrangement would permit either or both oi elevators Nos. 3 and 4 to be changed over to cause the cars to assist or replace the cars serving the uppermost zone and would permit either or both of elevators Nos. 5 and 6 to be changed over to cause the cars to assist or replace the cars serving the intermediate zone. The z one switches for each of elevators Nos. 3 and 4 would control the non-stop switch of that elevator in the same way as in Figure 2 while the two zone switches for each of elevators Nos. 5 and 6 would have their back contacts in series relation in the by-pass for contacts FR3 in the circuit for the coil of the non-stop switch. With such arrangement, and with the hook switches for the eleventh :door for elevators Nos. 5 and 6 connected to line -4- through service switches, the circuits of eitheror both of elevators Nos. 5 and 6 could also be thrown over to cause them to assist or replace elevators Nos. 1 and 2 in serving the uppermost zone.

By providing elevators Nos. 3 and 4 with additional zone switches like elevators Nos. 5 and 6, the circuits for elevators Nos. 3 and 4 could also be thrown over to cause eitheror both of these cars to assist or replace elevators Nos. 5 and 6 in serving the lowermost zone. With such arrangement, the zone switches for each of elevators Nos. 3 and 4 could be advantageously controlled by dial switches. Cars can be shifted from one zone to another as conditions warrant, and by shifting all cars in a zone to the zone above, these zones may be combined.

It is contemplated that many of the features of the invention disclosed may be used in connection with apparatus and circuits different from those specifically described and also in connection with other forms of elevator control. The system of control admits of many variations and many apparently widely different embodiments oi' the invention can be made without departure from the spirit or scope of the invention. It is therefore intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. An electric elevator system comprising: a plurality of floors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of up controls, one for each of said floors; means for each of said cars serving the upper zone for causing that car during its upward travel to stop in response to all up controls that are operated at the floors for which such controls are provided; and means for preventing each of said cars serving the lower zone from stopping in response to operated up controls at any time during its upward travel, regardless of the positions of the other cars.

2. An electric elevator system comprising; a plurality of floors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of up controls, one for each of said floors; a plurality of down controls, one for each of said floors; means for each of said cars serving the upper zone for causing that car during its upward travel to stop in response to up controls that are operated at the floors for which such controls are provided and also in response to an operated down control for a iioor in the upper zone at that :door under conditions where no control for a iloor in that zone above such floor is operated; and means for each of said cars serving the lower zone for causing that car in its upward travel to stop in response to an operated down control for a floor in lthe lower zone at that floor under conditions where no control for a oor in that zone above such door is operated but for preventing that car from responding to any operated up control.

3. An electric elevator system comprising; a plurality of floors forming an upper zone; a

plurality of additional Vfloors forming a lower zone; a plurality of elevator cars, at least one oi l which serves the upper zone and at least one other of which serves the lower zone; a plurality loi' up controls, one for each of said oors; a plurality of down controls, one for each of said iloors; means for each of said cars for causing that car, during its upward travel, to travel 'to the highest iloor in the zone served thereby for which a down control is operated, stop thereat in response to such control and be set for travel in the down direction; means for causing only said cars which serve the upper zone to stop inl response to up controls, during said' upward travel thereof; and a start control for each car manually operable from within the car to cause starting of the car.

4. An electric elevator system comprising; a plurality of iloors forming an upper zone; a plurality of additional iloors forming a lower zone; a plurality of elevator cars, at least one of which serves .the upper zone and at least one other of which serves the lower zone; a plurality of up controls, one for each of said floors; a plurality of down controls, one for each o1' said iloors; means for each of said cars for causing that car, during its upward travel, to travel to the highest floor in the zone served thereby for which a down control is operated, stop thereat in response to such control and be set for travel in the down direction; means for causing only said cars which serve the upper zone to stop, during said upward travel thereof, at intervening floors in response to up controls for such iloors; means for 'causing each of said cars, during downward travel thereof, to stop in response to down controls for iloors below the car at the corresponding floors; and a start control for each car manually operable from within the car to `cause starting of the car.

5. An electric elevator system comprising; a plurality of floors forming an upper zone; a plurality of additional oors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other oi which serves the lower zone; a plurality of up hall buttons, one at each of said floors; a plurality of down hall buttons, one at each of said iloors; means for each of said cars forV causing that car, during its upward travel, totravel to the highest floor in the zone served thereby for which a down hall call is registered, stop thereat in response to such call and be set for travel in the down direction; means for each of said cars which serves the upper zone for causing that car, during said upward travel thereof, to stop at intervening floors in response to up hall calls for such floors; means for each of said cars which serves the lower zone ior preventing that car, during said upward travel thereof, from stopping at intervening iioors in response to up hall calls for such floors; means for causing each of said cars, during downward travel thereof, to stop in response to down hall calls for iioors below the car at the corresponding oors; mechanism for each car for causing the order of stops of that car to be in the natural order of iloors; and a start control for each car manually operable from within the car to cause starting of the car after each stop.

6. An electric elevator system comprising; a plurality of oors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of up hall buttons, one at each of said oors; a plurality of down hall buttons, one at each of said floors; a plurality of car buttons, one for each of said floors, in each of said cars serving the upper zone; a plurality of car buttons, one for each of said floors of said lower zone, in each of said cars serving the lower zone; means for each of said cars vfor causing that car, during its upward travel, to travel to the highest floor in the zone served thereby for which a car call for that car or down hall call is registered, stop thereat in response to such call and be set for travel in the down direction; means for each of said cars which serves the upper zone for causing that car, during said upward travel thereof, to stop at intervening iioors only in response to ear calls for that car and up hall calls for such floors; means for each of said cars which serves the lower zone for causing that car, during said upward travel thereof, to stop at intervening floors only in response to car calls for that car for such iloors; and a start control for each car manually operable from within the car to cause starting of the car after each stop.

7. An electric elevator system comprising; a plurality of floors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of hall buttons, one at each of said floors; means for each of said cars serving the upper zonev for causing that car to stop at floors in the upper zone in response to calls registered by hall buttons at such floors; means for each of said cars serving the lower zone for causing that car to stop at iloors in the lower zone in response to calls registered by down hall buttons at such floors; means for preventing each of said cars serving the lower zone from responding to calls registered by hall buttons at floors in the upper zone; means for changing the floors forming the zones; and a start control for each car manually operable from within the car to cause starting of the car after each stop.

8. An. Aelectric elevator system comprising; a plurality of floors forming an upper zone; a plurality of additional iloors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of down hall buttons, one at each of said floors; means for each of said cars serving the upper zone for causing that car during its downward travel to stop rst at floors in the upper zone and thereafter at floors in the lower zone in response to calls registered by down hall buttons at such floors; means for each of said cars serving the lower zone for causing that car, during its downward travel, to stop at oors in the lower zone in response to calls registered by down hall buttons at such floors; and means for preventing each lof said cars serving the lower zone from responding to calls registered by down hall buttons at floors in the upper zone.

9. An electric elevator system comprising; a plurality of floors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of hall buttons, one at each of said iloors; a plurality of car buttons, one for each of said floors, in each of said cars serving the upper zone; a plurality of car buttons, one for each of said floors of said lower zone, in each of said cars serving the lower zone; means for each of said cars for causing that car, during its upward travel, to

travel to the highest floor in the zone served.

thereby for which a car button for that car or hall button is operated, stop thereat in response to such button and be set for travel in the down direction; means for preventing each of said cars serving the lower zone from continuing its travel in the up direction to a floor in the upper zone in response to a hall button for such floor; and a start control for each oar manually operable from within the car to cause the starting of the car after each stop.

10. An electric elevatorl system comprising; a plurality of floors forming an upper zone; a plurality of additional oors forming a lower zone; aplurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality of up hall buttons, one at each of said floors; a plurality of down hall buttons, one at each of said oors; a plurality of car buttons, one for each of said iloors, in each of said cars serving the upper zone; a plurality of car buttons, one for each of said floors of said lower zone, in each of said cars serving the lower zone; means for each of said cars for causing that car, during its upward travel, to travel to the highest loor in the zone served thereby for which a car call for that car or down hall call is registered, stop thereat in response to such call and be set for travel in the down direction; means for each of said cars which serves the upper zone for causing that car, during said upward travel thereof, to stop at intervening floors only in response to car calls for that car and up hall calls for such floors; means for each of said cars which serves the lower zone for causing that car, during said upward travel thereof, to stop at intervening iloors only in response to car calls for that car for such oors; means for preventing each of said cars serving the lower zone from travelling to a floor in the upper zone to respond to a hall call for such floor; and a start control for each car manually operable from within the car to cause starting of the car after each stop.

l1. An electric lelevator system comprising; a plurality of floors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator cars, at least one of which serves the upper zone and at least one other of which serves the lower zone; a plurality oi up hall buttons, one at each of said floors; a plurality of down hall buttons, one at each of said iloors; a plurality of car buttons, one for each of said oors, in each of said cars serving the upper zone; a plurality of car buttons, one for each of said floors of said lower zone, in each of said cars serving the lower zone; means for each of said cars for causing that car, during its upward travel, to travel 'to the highest floor in the zone served thereby for which a car call for that car or down hall call is registered; stop thereat in response to such call and be set for travel in the down direction; means for each of said cars which serves the upper zone for causing that car, during said upward travel thereof, to stop at intervening floors only in response to car calls for that car and up hall calls for such floors; means for each of said cars which serves the lower zone for causing that car, during said upward travel thereof, to stop at intervening oors only in response to car calls for that car for such floors; means for causing each ot said cars, during downward travel thereof, to stop in response to car calls within that car and down hall calls at the corresponding floors; mechanism for each car actuated in accordance with sequence o! iloors for causing the order oi stops oi that car to be in the natural order of iloors; and.a start control for each car manually operable from within the car to cause starting of the car after each stop.

12. An electric elevator system comprising; a plurality of iloors forming an upper zone; a plurality of additional floors forming a lower zone; a plurality of elevator tears, at least one or which serves the upper zone and atleast one other of which serves the lower zone; a plurality of up hall buttons, one at each oi saidiloors; a plurality of down hall buttons, one at each of said floors; a plurality of car buttons, one for each of said floors, in each of said cars serving the upper zone; a plurality of car buttons, one for each of said floors of said lower zone, in each of said cars serving the lower zone; means for each of said cars for causing that car, during its upward travel, to travel to the highest iloor in the zone served thereby for which a car` button in that car or down hall button is operated, stop thereat in response to such button and be set for travel in the down direction; means for each of said cars which serves the upper zone for causing that car, during said upward travel thereof, to stop at intervening oors only in response to operated car buttons within that car and up hall buttons for such floors; means for each of said cars which serves the lower zone for causing that car, during said upward travel thereof, to stop at intervening iloors only in response to operated car buttons in that car for such iloors;'means for causing each of said cars, during downward travel thereof, to stop in response to car buttons within that car and down hall buttons that are operated, at the corresponding floors, the upper zone cars, after responding to down hall buttons in the upper zone, thereby assisting the lower zone cars in responding to down hall buttons in the lower zone; mechanism for each car actuated in accordance with the sequence of iloors for each direction of travel for causing the order of stops of that car for each direction of travel to be in the natural order of floors, regardless of the order in which the buttons in response to which the stops are made are operated; and a start control for each car manually operable from within the car to cause starting of the car after each stop.

13. An electric elevator system in which a plurality of elevator cars are provided, each stopping at iloors in response to calls registered by push buttons and restarted after each stop in response to the manual operation of a start control within the car, characterized in that the iioors are grouped into at least two zones, with at least one of the cars serving the upper zone and at least one other of the cars serving the lower zone and that means are provided for preventing the lower zone cars from serving floors in the upper zone and in addition means are provided for changing the floors forming either zone.

14. An electric elevator system in which a plurality of elevator cars are provided, each stopping at iloors in response to calls registered by push buttons and restartedafter each stop in response to the manual operation of a start control within the car, characterized in that the oors are grouped into at least two zones, with at least one 0f the cars serving the upper zone and at least one 

